Aspirating devices frequently employ a suction pump, a collection container and a drain tube to facilitate the removal of various fluids from a body cavity, surgical site, or wound site. The drain tube transfers the various fluids from the body site to the collection container under the influence of the vacuum created by a suction pump.
In practice, use of such aspirating devices can result in the transmission of excessive levels of vacuum to the body site. This is to be avoided because the application of high suction levels at the body site can result in injury or damaged tissue adjacent to the area of placement of the drain tube at the body site. In some instances, openings in the drain tube at the body site may come into contact with body tissue thereby blocking off some or all of such openings and resulting in the application of an increased and undesired negative pressure to the body tissue which covers and blocks such openings and risking injury or damage to such tissue.
Attempts have been made to overcome this deficiency. specifically, drain tubes have been designed to provide a vent lumen therein through which fresh air is conducted to the distal end of the tube, thus relieving excessive vacuum. However, there remain innumerable instances where drain tubes not having such a self-relieving features are medically necessitated.
Accordingly, there exists a need for a means of regulating the vacuum of a vacuum pump in an aspirating device to prevent the application of excessive vacuum at the body site to prevent injury at the body site which might otherwise result from said excessive vacuum.